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How long is a wavelegth for about 85-90 hrtz?? I can't figure out why I have such a sharp freakin dip at this frequency...I have tried underlapping and overlapping, and that doesn't seem to help. i tried reversing the polarity of the subs, but that then creates a small dip at the x-over frequency.

the only thing I can think of is that I hold my meter in a bad spot where the two midbasses cacel each other out, and cancel each other out even more with the sub bass on.

 
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roughly about 12 - 13 feet.

 
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cool, thanks

 
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speed of sound at sea level = 1129 feet / second = c

frequency = 85 Hz = 85 cycles/second = f

wavelength = unknown = λ (greek letter lambda)

v = fλ

or

λ = v/f

so

λ = 1129/85 = 13.28 feet

now dont ever ask me how to do that again mike =)

 
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i love the way ludlam drops knowledge like that! (not being sarcastic)

 
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< ----------------- future high school physics teacher (bout a year or two, depending on money)

my goal is explaining it once thoroughly so ill never have to do it again, but it never works....

 
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Damnit, this happens to me all the time in school! I had the right answer but didn't show my work! Arggggg.

Just incase anyone wrote down that forumla (which you may want to do) that C is supposed to be a v, it's just a typo.

 
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no, the c is a c, because its a constant

when dealing with absolutes such as wavelengths in light and or sound, one uses c

if you just used it as a general formula, then v would be proper

 
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oh, mike, are you still running your q-forms free air? like have you at all sealed up the backs?
if so, that may be your issue


EDIT:

just remember you have the kicker rmb6's

im still thinking it has something to do with those guys

 
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Oh, my bad. I saw it as the general formula and thought since the letter c is right next to the v on the keyboard. . .

 
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Hmm, Good topic. I won't hijack though, I'll start a new thread.

 
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Yeah, Maybe...I did not have a dramatic drop with the Infinitys, but the Infinitys did not thump nearly as hard. The RMB6s kick but in the 110-140 region, but start dropping quickly at 100 with the x-over at 70 hrtz.

 
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i'm impressed, you even took the time to use the real lambda symbol

 
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would you happen to have any t/s parameters for those kickers on hand?

 
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He probably wouldn't considering kicker only discloses T/S for their "sub" woofers

 
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Here is the technical info for the RMB 6. It has a lot more info then the actual manual, but I don't see any T/S parameters...only a lot of graphs

 
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I'll prolly end up boosting 80hrtz with a high Q, but I don't like to because it will add sub bass and prolly cancel out the mids even more.

 
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Technical manual = no T/S though.

 
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You know what it could be...My subs response drops off the face of the earth above 70 hrtz ever since i ported them (although I am very happy with how falt the response is from 35-65 hrtz...like +/- 1 db). The Mids in in the door prolly start to drop at around 100hrtz. So maybe neither of my speakers (Subs and Mids) can adequately cover 85-95 hrtz.

I can try two things if this is the case...either overlap a lot, or boost a few DBs at 80 (but this also boost the surrounding requencies, and my loudest fequencies are at the 120 and 50 hrtz areas).

FYI, my mids alone will play at 89 dbs at 15 on the volume, but with the bass on it plays at 85-86 dbs. I have tried to make all of my midbass between 90-94, so 90 is less.

...man, i like to ramble

 
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i have never been impressed by the kicker rmb6's

pm me though or get me on aim, i might be willing to lend you some drivers to test in your doors to see if it helps

 
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Thanks Lud, I wouldn't want to rust your drivers in my leaky as door...anywayz, I bought them because they were cheap and I didn't want to spend a lot for midbass in my door...In a few months I may think about some new ones...but I am actually really happy with the kickers (even though the speakers are not as solid as my other speakers), but they play resonably flat, except for a peak at around 125 (which I like), and a dip at 90 (that I don't like)...they are funny though because they peak again at 60...so even thoug they are x-over at 70, they have the same output at 60...but they drop from 100 to 70hrtz

...and you know me, I hate the install part of audio...but I will check with yall for suggestions if I get new drivers...midbasses are not too expensive...but I did get those kickers for only $109.

 
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are you independently amping them?
or using a passive with the ti's?

 
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I have the speakers set up as follows:

PG Ti 600.2 for Ti Elite Speakers (185 hrtz and up)
JBL PX 600.2 for Kickers (70hrtz-185hrtz)
JBL BP1200.1 (JBL BPX 1100.1 sitting on couch waiting to be installed) for Maxes (20-80hrtz with a 20 hrtz subsonic). I have tired the lowpass at 60 and 70 hrtz, and I tried it at 80hrtz and I like the bass midbass transition a lil better. However, my bass out put starts to drop at 65 hrtz and above.

I like the way it currently sounds, so I am gonna try it for a few days and see how it goes. I should really wait until install my new amp before i do my "final" tuning.

 
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hmm
maybe
you could try a dctt enclosure